E. Nesbit said this quote

Grown-up people find it difficult to believe really wonderful things, unless they have what they call proof. But children will believe almost anything, and grown-ups know this. That is why they tell you that the earth is round like an orange, when you can see perfectly well that it is flat and lumpy; and why they say that the earth goes round the sun, when you can see for yourself any day that the sun gets up in the morning and goes to bed at night like a good sun as it is, and the earth knows its place, and lies as still as a mouse. Yet I daresay you believe all that about the earth and the sun, and if so you will find it quite easy to believe that before Anthea and Cyril and the others had been a week in the country they had found a fairy.